Indeed, the only point of the links for me is that they generate worthwhile discussion. (Which is why I tend to flag political links and such that have been proven to not generate worthwhile discussions, whether or not the article itself is worthwhile.)
Especially because HN shows no summary or anything of the linked article: I'm not going to click on a link if the only information about it that I have is an (often purposefully) abstruse title and a domain name. Once there are a few comments that give me an actual impression of what the article is going to be, then maybe I'll go back and actually read it.
I really, really enjoy the comments on this site.